Routine beta-blocker therapy after myocardial infarction (MI) has long been recommended regardless of left ventricular ejection fraction (LVEF). Evidence supporting this approach in patients with preserved systolic function remains limited. A post hoc analysis of the REBOOT trial, published in EuroIntervention, examined the ischemic safety of withholding or withdrawing beta blockers at hospital discharge in this population.

The analysis included patients with MI and LVEF greater than 40% who were randomized at discharge to beta-blocker therapy or no beta blocker. Short-term ischemic events were assessed at 3 months, and recurrent ischemic outcomes were evaluated during follow-up. The composite ischemic endpoint included cardiac death, reinfarction, sustained ventricular tachycardia or ventricular fibrillation, resuscitated cardiac arrest, and unplanned revascularization.

Among 8,401 patients with available beta-blocker history, 12.1% were receiving chronic beta-blocker therapy before the index MI. Withholding or withdrawing beta blockers was not associated with increased short-term ischemic risk. The hazard ratio was 1.13, with a 95% confidence interval of 0.74 to 1.72. Over a median follow-up of 3.7 years, recurrent ischemic events remained comparable between groups, with a hazard ratio of 0.98 and a 95% confidence interval of 0.82 to 1.16.

In patients receiving beta blockers before the index MI, randomization to no beta blocker at discharge was not associated with a higher risk of recurrent ischemic events during follow-up. The hazard ratio was 0.93, with a 95% confidence interval of 0.64 to 1.34. These findings indicate that beta-blocker withholding or withdrawal after MI does not increase short-term or long-term ischemic risk in patients with preserved LVEF.